Abstract: In order to explore the effects of cultivation density on the growth of Larix gmelinii plantations, the differences in growth characteristics and environmental conditions of Larix gmelinii plantations in Lanzhou area of Gansu Province were investigated under different cultivation densities, and the effects of cultivation density on the growth of Larix gmelinii plantations were discussed.The results showed that tree height, DBH, crown width, canopy density, litter thickness and shrub coverage of Larix gmelinii were significantly affected under different cultivation densities. With the increase of density, the height of the deciduous Larix gmelinii increased first and then decreased, and the height of the tree under treatment 3 was 18.13 m. The DBH decreased gradually, and the maximum DBH was 16.83 cm under treatment 1. The crown width showed a gradually decreasing trend, which was the same as the change trend of DBH. The crown width of treatment 1（4.16 m） was the largest, and that of treatment 4（2.61 m） was the smallest.The canopy closure of Larix gmelinii plantation showed an increasing trend, and the highest canopy closure was 87.25% under treatment 4. The litter thickness increased gradually, and the maximum litter thickness was 8.36cm under treatment 4. The shrub coverage of Larix gmelinii increased first and then decreased. The maximum shrub coverage of Larix gmelinii under treatment 3 was 72.96%.It provides theoretical basis for Larix gmelinii cultivation.